Steel grating



Dec. 28 1926. 1,612,236

W. S. THOMSON STEEL GRATING Filed August 2, 1926 Patented Dec. 28," 1926.

UNITED STATES PATENT. OFFICE.

WILLIAM S. THOMSON, CHICAGO, ILLINOIS, ASSIGNOR TO KALMAN STEEL COM- PANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

STEEL GRATING.

Application filed August 2, 1926. Serial No. 126,694.

tively great strength isrequired to support the weight of hand trucks or vehicles.

The grating now in general use consists of parallel spaced-apart-strips with lattice members extending bet-ween and spacing said members, the lattice elments being riveted at their junction with the arall'el strips. The labor involved in the abrication of this grating is considerable, due to the multiplicity of punching and riveting operations.

In the design here proposed, the number of operations necessary to the production of other loaded the grating is materially reduced. Thedesign contemplates the provision of a plurality of spaced uniform notches in the strips and transverse spaced elements bent into zigzag form and adapted to be pressed into the notches in the strips. The notches are so shaped at their inner ends that the act of pressing the transverse eleme s therein serves to laterally distort or deflect such elements and thereby to permanently anchor the elements in the notches. Consequently the gratin is completed in three major operations; rst, the punching of the strips; second, the shaping of the transverse spacing elements; and, third, the pressing of the spacing elements into the openings in the strips.

The invention will be more readily understood by reference to the accompanying drawings, in which;

Fig. 1 is a plan View of a section of a.

grating constructed in accordance with my invention;

Fig. 2 is a sectional view on the line 2-2 of F1g. 1; -V Fig. 3 is a sectional view on the line 33 of Fig. 1; and

Fi 4 is a fragmentary detail showing the arm of notches in the strips.

The grating is composed of a plurality of arallel 'steel strips, A, having notches, 11, ibrmed therein at spaced intervals. The

shape of the notches is indicated in Fig. 4. The lower end of the recess is flared as at 12, 13, and the flared portion is divided by a tongue, 14, having a pointed extremity, 15, which projects toward the entrance opening of the notch. The transverse spacing elements B, are relatively shallow, compared to the depth of the parallel strips, and are bent into the zigzag form indicated. The portions, 16, that join the diagonal portions, 17, are preferably placed in abutting relation so that similar portions in two adjacent transverse members may occupy the same notch in a longitudinal strip. The portions, 16 of the transverse elements are normally fiat and are placed in the notches, 11, in that condition. However, upon the application of a force tending to seat the elements entirely. within the notches, the lower ends, 18, of the portions, 16, are laterally deflected as shown in Fig. 2, by contact with the wedge shaped tongue, 14, at the bottom of the notch. This lateral distortion of the metal of the transverse elements serves to securely anchor the transverse and longitudinal members of the grating andcffectually prevent any possible separation thereof in subsequent handling or use.

It will be noted that the notching of the longitudinal strips does not materially reduce the strength thereof relative to superposed loads; this for the reason that the upper portion of the strip is in compression and the notches are completely filled by the metal of the transverse elements. Thus a highly eflicient floor grating may be constructed simply and economically by the use .of common mechanical devices.v

transverse spacin elements bent into angular form, the ang es of two adjacent spaced elements being. arranged in abutting relation, and occupying the notches in said strips, said spacing elements being distorted at the point where they occupy the enlarged lower ends of the notches.

- 2. In a grating, the combination of longitudinal and transverse strips, one series of said strips having spaced apart notches flared attheir lower ends, an integral tongue projecting upwardly into the flared lower 1 In testimony whereof I have aflixed my 15 signature.

'WILLIAM s'. THOMSON. 

